Why is it important to check and possibly upgrade ventilation systems after building envelope upgrades?

Building envelope upgrades such as draftproofing (air sealing), installing new windows and upgrading insulation improve the air tightness of your home and keep the heat in more efficiently. However, an increase in airtightness may also increase the humidity levels of your home. It is important to have an adequate ventilation system to ensure that you have sufficient ventilation through your home to prevent moisture problems (e.g. condensation and mould).

Ask your energy advisor or contractor what ventilation system upgrades you will need for your home.

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